(a) Field of the Invention
The present invention relates to a method and an apparatus for transmitting a response (for example, hybrid automatic repeat request (HARQ) acknowledgement/negative acknowledgement) to an uplink data transmission through a downlink.
Further, the present invention relates to a method and an apparatus for transmitting a synchronization signal.
(b) Description of the Related Art
When a base station responds to a plurality of uplink transmissions transmitted by a plurality of terminals, responses (for example, HARQ-ACK/NACK) to each uplink transmission need to be transmitted several times.
As a result, a resource may be used inefficiently and a signaling overhead problem may occur.
Therefore, a method for tying up, by a base station, a plurality of responses (for example, HARQ-ACK/NACK) to a plurality of uplink transmissions and transmitting the tied up responses at a time is required.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.